A general view of Edinburgh Castle on February 7, 2012 in Edinburgh, Scotland. The castle dominates the city skyline was built on top of an extinct volcano, and has had a human settlement on the castle site since 900BC. (Photo by Jeff J. Mitchell/Getty Images)

An Edinburgh Fringe performer shows off his makeup on the Royal Mile, in the final weekend of this year's festival. The largest performing arts festival in the world has been running for the past three weeks and has enjoyed an increase in venues and visitors compared with previous years. (Photo by Jeff J. Mitchell/Getty Images)

The first tram is delivered to the Gogar tram depot on October 17, 2011 in Edinburgh, Scotland. The tram was delivered on a low loader which had driven from Irun, northern Spain and is the first of 27 trams expected to arrive at the depot over the coming months. Last month the Scottish Government intervened to oversee the troubled Edinburgh trams project assigning project managers from Transport Scotland to work with contractors Bilfinger Berger. (Photo by Jeff J Mitchell/Getty Images)

Shaun Gibson prepares some of the 5.5 tonnes of fireworks at Edinburgh Castle ahead of the city's Hogmanay celebration on December 29, 2011 in Edinburgh, Scotland. Over 2,800 individual fireworks from six specialised firing panels will be launched during the display over Edinburgh Castle and gardens. (Photo by Jeff J Mitchell/Getty Images)

Edinburgh Zoo is proud to introduce this baby three-banded armadillo Rica who was born to mum Rio and dad Rodar in Edinburgh, Scotland, UK on Sunday 24 August 2014. A tiny 81g at birth and around the same size as a golf ball, Rica is a female three banded armadillo who has grown rapidly in her first month, already quadrupling in weight. (Photo by SWNS/ABACAPress)

Princess Elizabeth with her husband Prince Philip Duke of Edinburgh and their children Prince Charles and Princess Anne. (Photo by Keystone/Getty Images). August 1951

Zoo keeper Ross Poulter holds a White's Tree Frog in Edinburgh Zoo's new tropical forest zone on September 9, 2011 in Edinburgh, Scotland. The Brilliant Birds Exhibit which brings together beautiful and rare birds from all over the world is now more colourful and unusual, with the unveiling of the zoo's new tropical forest zone bringing together a collection of vertebrates, invertebrates and amphibians for the very first time. (Photo by Jeff J Mitchell/Getty Images)

Men dressed as Vikings lead the torchlight procession as it makes its way along Princess Street for the start of the New Year celebrations December 30, 2011 in Edinburgh, Scotland. Thousands of people joined in the torchlight procession, which is followed by the burning of a Viking long ship, to mark the start of Edinburgh's Hogmanay celebrations. (Photo by Jeff J. Mitchell/Getty Images)